Oops - typo there, reducing the colors from 256 to *125* reduced the image size by about 15%.
On Tue, May 18, 2021 at 12:11 PM Richard Greenwood < [email protected]> wrote: > Bob - I think GD was quite unpopular with the developers. Thomas Bonfort > was pretty adamant about removing it. I'm hoping that there may be options > in AGG. > > Seth - FORMATOPTION "COMPRESSION=9" only reduced the size by about 3% in > my lines and text test case. > > Even - the default AGG/PNG8 has QUANTIZE_FORCE=on and QUANTIZE_COLORS=256. > I think I remember you saying somewhere that reducing the number of colors > mostly just reduced the pallet size and that's pretty much what I see. e.g. > reducing the pallet from 256 to 15 colors reduces the image size by about > 15% in my lines and text test. > > Thanks all for the suggestions. > Rich > > > On Tue, May 18, 2021 at 11:49 AM Even Rouault <[email protected]> > wrote: > >> Forcing paletted images using QUANTIZE_FORCE=on and decreasing the number of >> colors with QUANTIZE_COLORS can also help: >> >> FORMATOPTION "QUANTIZE_FORCE=on" >> FORMATOPTION "QUANTIZE_COLORS=200" >> >> Le 18/05/2021 à 19:30, Seth G a écrit : >> >> I've not used it but the following might help for the AGG/PNG driver: >> >> FORMATOPTION "COMPRESSION=9" >> >> https://mapserver.org/mapfile/outputformat.html >> >> The default is 6. >> >> -- >> web:http://geographika.co.uk >> twitter: @geographika >> >> >> On Tue, May 18, 2021, at 7:16 PM, Basques, Bob (CI-StPaul) wrote: >> >> All, >> >> >> >> I know the GD stuff has been a long running conversation in the MapServer >> realm, but does this indicate that maybe discussing something on adding GD >> back in might be prudent? Or are there methods to get down to these >> previous files sizes with the newer approaches? >> >> >> >> I have the same concerns related to image size from the performance side, >> and running on Mobile in our case. >> >> >> >> Bobb >> >> >> >> >> >> *From: *mapserver-users <[email protected]> >> <[email protected]> on behalf of Richard Greenwood >> <[email protected]> <[email protected]> >> *Date: *Tuesday, May 18, 2021 at 11:50 AM >> *To: *"[email protected]" <[email protected]> >> <[email protected]> <[email protected]> >> *Subject: *[mapserver-users] anti-aliasing (was differing image size >> with different mapserver versions) >> >> >> >> *Think Before You Click: *This email originated *outside *our >> organization. >> >> >> >> Thanks to several helpful replies to my previous thread I know that the >> increased image size between MapServer 6 with the GD driver and MapServer 7 >> with the AGG driver is due to differences in anti-aliasing (and lack of) in >> the two drivers. (AGG features anti-aliasing and sub-pixel resolution >> <https://en.wikipedia.org/wiki/Anti-Grain_Geometry>). >> >> >> >> Gamma setting from 0-1 affects the size of a filled polygon layer by a >> factor of almost 3x. But gamma has no effect on text, lines, and polygon >> outlines. So images comprised of these types of features are approximately >> 2x larger with the AGG/PNG8 driver than with the GD/GIF driver. >> >> >> >> Where else should I be looking to reduce my images sizes? I serve rural >> areas with poor internet so in my case, smaller image sizes are more >> important than higher quality images. >> >> >> >> Thanks, >> >> Rich >> >> >> >> -- >> >> >> Richard W. Greenwood, PLS >> www.greenwoodmap.com >> >> >> _______________________________________________ >> mapserver-users mailing list >> [email protected] >> https://lists.osgeo.org/mailman/listinfo/mapserver-users >> >> >> >> _______________________________________________ >> mapserver-users mailing >> [email protected]https://lists.osgeo.org/mailman/listinfo/mapserver-users >> >> -- http://www.spatialys.com >> My software is free, but my time generally not. >> >> _______________________________________________ >> mapserver-users mailing list >> [email protected] >> https://lists.osgeo.org/mailman/listinfo/mapserver-users >> > > > -- > Richard W. Greenwood, PLS > www.greenwoodmap.com > -- Richard W. Greenwood, PLS www.greenwoodmap.com
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